Cable carriers are well known in the industry and, although called cable carriers, carry flexible hoses, cables, wires, or any elongated energy transmission conduits that can bend around the U-bend of the cable carrier as it moves back and forth. As is well known, one end of the cable carrier is fixed, and the other end of the cable carrier is attached to a movable head of a machine, for example of a machine tool, with a U-bend of the cable carrier in between an upper self supporting straight run and a lower straight run of the carrier so that the relative length of the two runs varies as the movable end of the carrier moves linearly. To achieve this function, the cable carrier is self supporting in a generally straight configuration in one direction, but not the opposite direction.
U.S. Pat. Nos. 5,108,350, 5,184,454, and 6,107,565 disclose cable carriers made up of two parallel chains of side links interconnected end-to-end, which permit pivoting between the lengths in only one direction from a straight or slightly cambered extended position. The links may be molded with limiting members of various sizes to create carrier chains with a variety of pivot radii. Carrier chains of this type, made of multiple pieces which may be either made of plastic or metal or both, are well known.
Also known in the prior art are carriers with longitudinally continuous members, such as flat metal covers, or bands which may be concave in the lateral (width-wise) direction, like a wind-up tape measure tape. For example, Merker U.S. Pat. No. 3,161,205 discloses a longitudinally flexible band with cable supporting members thereon having rollers for movement along parallel rails which support and guide the carrier. Weber U.S. Pat. No. 3,330,105 reveals an enclosed cable carrier with cylindrical cross-lengths and lateral separators, through which is inserted a sheet metal band cover between separating web members and roller members which extend between the opposite side plates. Moritz U.S. Pat. No. 4,084,370 discloses another carrier using a sheet metal band as a cover.
Carriers with individual or continuous cross-links or covers fixed to the side plates require many parts, making manufacture, assembly, and disassembly more difficult. Carriers with individual or continuous covers, whether or not integrally molded with the side plates, can have pinch points, which also can permit dirt and debris to enter the carrier. Sheet metal band covers, whether flat or arched laterally, can have sharp edges which can abrade the cables and hoses, require an open joint at the sides, and can be difficult to handle in long sections. In addition, with such bands, separate cross-links are typically provided to hold the side chains in lateral and transverse alignment.